Question
Write a note on half-life of a radioelement.
✓
Answer
- Half-life of a radioelement $\left(t_{1 / 2}\right)$: It is the time needed for a given number of nuclei (atoms) of radioelement to decay exactly to half of its initial value.
- Each radio isotope has its own half-life.
- Half-life of a radioelement can be expressed in seconds, minutes, hours, days or years.
- Mathematical expression for half-life of a radioelement can be given as,
$t_{1 / 2}=\frac{0.693}{\lambda}$
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Answer:
Given: $N _0=100$,
$
N=100-65=35 \text {, }
$
$
t=4.2 d
$
To find: $t_{1 / 2}$
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To find: $t_{1 / 2}$
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